Engine cylinder block



April 9, 1935. F. G. SHOEMAKER ENGINE CYLINDER BLOCK Filed Jan. 18, 1933 2 Sheets-Sheet 1 as w wv I my April 9, 1935- F. G. SHOEMAKER ENGINE CYLINDER v BLOCK Filed Jan 18, 1933 2 Sheets-Sheet 2 fiea'jfloemaket Patented Apr. 9, 1935 UNITE-D1 STATES ENGINE CYLINDER-BLOCK Fred- G; Shoemaker, Ferndale, -Mich.;-assignor; by

mesne assignments," to General Motors" 001' poration; Detroit; Mich., a corporation of Dela-1 ware I 1 Application January-18, 933;'Se"rialNo..652,a0s

" '1 Claims.-- (01. 123-473. 1

This inventionrelates to structures which while adequately strong; are oflesscubic-materialacontentand lighter in weight than equivalent struc.-- tures now-usually made in moulds by casting ,5 vowingwtothelimitations of [the casting-process.

It further ,relates. to the mannerof dividing or splitting of the structurev into separate parts which .cancbe simply produced and then .assembled together preferably: by press fits. upon each other. linto a built up structure adapted .to be soldered, .-.brazed, or-welded into a single unit. Theinvention .is also ,applicable where the complicatedlnaturerofthe mould-makes a casting more expensive than the alternative built up structure.

More particularly, the invention relatesztorbuilt up steel cylinders, :especially .for internalcombustion engines. In addition: .to..- the lighter weightrof such :cylinders there is Lan additional advantageain that. they permit of a higher. power output without 5 thermal distress :than is "possible with the necessarily much thicken. construction of 2 the usual: cast iron cylinders. It will 1063RP- preciated that: thin steel cylinder. walls 1 permit the flow-of. waste heat ata much: greater :rateto the cooling mediumwhere it is dissipated-,- than is possible @with' the thicker :cast:ironcylinder. walls.

The rate of heat development inntwo-cycle-engin'es :particularlyi may-be: so high 1that=the poor rate: :of; heat-wflow through cast-iron: walls and other parts exposedrto heatisa distinct limitation onthe--power output otherwise; obtainable.

In such circumstances: the 1 use of thin steelor cylinder walls and other-partsrwill enable [the :attainment: ofva higher-power :output:

.Themaforementioned advantages" of built: up steel cylinders make themrverygsuitable dfor :the propulsion-or.aircraft where -lightness 1of weight with maximum" power output; is of prime importance;

Each cylinderwith sits individuabwaterjacket will preferablycbe a complete unit-as -faras: possible; and adapted- :for combining: :in: r a single or multiacylinder block of". any desired-.numberof cylinders withtheuse .of as few additional parts as possible; andv preferably only: top gand-bottom plates or deck flangesv connecting-any number of cylinders: togetheri tou make a single on a multicylinder :block.:- The objector the invention :is an: engine-cylin- :der:.blockzrwhich- :while 1 of adequate strength-iwill belightereand thinnen-than could be-produced-as a single wholelsuchas .the' usual' ..cast-. cylinder block, with the *added' advantage-that it will permit: of much more rapid aextractionzorr dissi- 1 potion of: theizawaste. heat of the engine: cycle which is'not converted intowork, or of therwork whichis converted into heat any engine to which it may be applied Itis a further .objectof the invention toattain theabove object by thedivisionof the-complete cylinder assembly withiall necessaryports water jackets, and. flanges, etc.,- into component. parts which can be simply produced and easily assembled. into a built up cylinder block,.having.regard to themethod. of.v joining, as for instance intthe case of brazing, the accessibility of vthe jointsfor the placement of. the brazingmetal oralloy which may be applied inth'eform of wireor ribbon,

powder paste or by spraying;

A.still..further. object of the; invention is. to formlthe component. parts. of the. structurev as far as possible .of .stampings which can bevcheap- 1y produced .01. material such as. sheet-1 steel, all

the parts being assembled. together preferably by the joints lwhichare required to. .be brazed, in

any suitable'form, i. e., wire, ribbon, powder paste, orit may besprayed ones a powder mixed with clear lacquer to.v hold it; on the. steel... Thewhole assembly isthen heatedt o the requiredlbrazing temperature iii-a reducing atmosphere. The reducing=atmosphere cleans the surface of thesteel and the melted copper is .drawn into all thejoints bodiment of cylinder units in blocks of" any 'desired multiple'of cylindersitis desirable to provide each cylinder with its own water jacket,

some means has to be-provided for cooling the otherwise 'uncOQled-bridgebetween the 'twocylinders having a common combustion'chambe'r of: a' U type 1 engine which formspart of- 1 a wall of the combustionchamber and isexposed :to

perhaps: the hottestv "zone .:.of .the': burning gases.

This has been efiected by the use of. a water .jacket. extension pieceservingto bridge and connect .togetherethe water jacketsrofxeach pair of cylinders having a common combustion chamber.

The water jackets do not extend as far upwards as the top deck flange of the cylinders which forms also the bridge to be cooled between each pair of cylinders in order that a single piece which is the water jacket extension piecemay serve at one and the same time to bridge and connect together the water jackets of each pair of cylinders and to form a flaredout extension to each of the cylinder water jackets for connection to the periphery of the top deck flange" to effect the top closure of the cooling space. It will be appreciated that since thetop deck flange forms the aforementioned bridge between the cylinders, it should be as thin as possible, consistent with adequate strengthin orderthat the rate of heat flow to the cooling medium may be as high as possible. The top deck flange is, in fact, made as thin as possible and is made stronger or thicker at other parts other than in. the region of the bridges as may be required and hereinafter describedj In such an engine, piston controlled ports for inlet of air or charge mixture are provided in one cylinder and similar exhaust ports are provided in the othercylinder. The cylinder surfaces between the ports, i. e., the port bridges and in the case of the exhaust ports, the material forming the surface areas of the ports themselves is exposed to the heat of the hot combustion gases and must be cooled. In an engine provided with a cooling jacket spaced from the cylinder barrel the ports must be carried or continued through the cooling jacket and the cooling mediummust flow through the bridges between the ports.

This may be effected by providing the cylinder barrel with an integral sleeve portion partitioning the clearance space between the cylinder barrel and the water jacket in the zone of the ports, the ports being milled as conduits through the sleeve portion and the bridges between the ports being grooved to ,form with the water jacket, ducts or conduits for the flow of cooling water between the ports. 7

Alternatively, the sleeve portion might be on the water jacket internal thereof and integral therewith inwhich case the cylinder barrel would,

together with the grooves in the bridges between the ports, form the ducts or conduits for the flow of cooling water between the ports.

Alternatively, the'sleeve. portion may be a unit, i. e., a port piece made separately from the cylinder barrel and the cooling jacket as shown in the accompanying drawings in which it is a ring.

As shown, the port conduits aremilled through the'ring andthe'bridges between the port conduits are grooved to form with the water jacket, ducts or conduits for the flow of cooling water between the ports. v

Fi ure 6.

Figure 6 is an enlarged part-plan View of the cylinder block with parts broken away.

Figure is an enlarged section on line 'l 1 of Figure 1.

Figure 8 is a section onlinev 8-8 of Figure 7. The two cylinder barrels l and 2 which may be termed inlet and exhaustcylinders', respecouter pieces.

tively, consist of seamless steel tubing machined inside and out.

The necessary rectangular port openings 3 in the inlet cylinder barrel and 4 in the exhaust cylinder barrel are next milled in the cylinder walls. A forged hold down flange 5 common to the two cylinders is slipped over the tops of the two barrels and pressed down against a shoulder 5 on each barrel. The two barrels l and 2 and the flange 5 are now firmly held together and can be treated as a unit. The port pieces 1 for the inlet cylinder, and 8 for the exhaust cylinder are each ring shaped in the embodiment of the invention illustrated and are machined from a solid ring. The conduits 9 in the inlet port ring I for the inlet cylinder and which coincide with the ports 3 in the barrel I are milled directionally tangential to themedian circumference of the cylinder bore as shown in Figure 3 so as to give rotational flow to the incoming charge or air in a clockwise directionas seenin Figure 3. The

"conduits I!) in the exhaust port ring 8 for the exhaust cylinder and'which coincide with the ports 4 in the barrel 2 aremilled directionally as shown in Figure 8 to give-easy egress of the exhaust gases in the outlet direction. The spaces between the conduits are milled away as shown at H and are slotted through the ring at I2 leaving only the thickness of the cylinder barrel itself between the cylinder barrel bore and the cooling medium.

These port rings are slipped over their respective cylinder barrels and pressed down until located by a shoulder on the barrel, the respective port and conduit openings in barrels and rings coinciding. l

It should be noted that the bores of the flange 5 are slightly greater than the outer diameter of the shoulders on which the port rings '1 and 8 rest, so that the flange 5 maybe slipped over these shoulders and pressed down against the shoulders 6 on each barrel.

' Water jackets l3 and I4 consisting of seamless steel tubing machined inside and out with port openings to coincide with those in the port rings 1 and 8 are now pressed over the port rings and pressed down over a shoulder l5 onthe lower hold down flange 5.

Intake and exhaust port chambers Iii-and I1 are next assembled. Each chamber is made in two halves divided on the line l8 of Figure 1 with a lap joint. Each chamber may be split in a vertical plane on the-port flange side at 19. To provide for the cooling'of the exhaust port chamber I! inner pieces 22- and 23 are placedin the chamber to be subsequently-clamped between the chamber and the cylinder water jacket, leaving a water space of 'aboutbetween innerand The-port flanges =20 and 2| are pressed over the pieces forming the chambers. The port chambers are then slipped-over the tops of the water jackets of-ltheirrespective cylinders and'pressed down onto a locating shoulder into 'to provide the necessary stock for tapped stud holes in cases where a removable cylinder head is desired. The studs are provided with flats engaging thesides of the channel section flange to prevent them from turning. This uppercylinder flange together with an upper water jacket extension '28 of die pressed sheetsteel is next assembled by pressing the flange into the jacket extension. The assembly is then pressed into place over the tops of the barrels and water jackets.

This top unit unites the water spaces of both barrels and completes the cylinder block with the exception ofthe removable cylinder head.

The holes 29 in the upper cylinder flange provide water connections between the cylinder jacket and cylinder head.

I claim:

1. In a built up engine cylinder block, in combination a cylinder barrel of steel tubing, a water jacket of steel tubing surrounding and forming a cooling space around the cylinder barrel, a sleeve portion partitioning the cooling space, port conduits through the sleeve portion for the flow of fluid into or out from the cylinder, and grooves in the exterior of the sleeve portion between the port conduits, forming together with the water jacket, cooling spaces and ducts for the flow of water from one side to the other of the partitioned cooling space.

2. In a built up engine cylinder block, in combination, the following separately produced units, a cylinder barrel provided with ports for the flow of fluid therethrough, a tubular Water jacket spaced from the cylinder barrel and provided with similar ports, a port ring filling that part of the annular space between the cylinder barrel and the Water jacket in the zone of the ports having conduits and ducts formed therein, which, together with the cylinder barrel and the, water jacket form port conduits for the passage of fluid through the water jacket to the engine cylinder and ducts formed wholly in the port ring for the passage of the water of the jacket between the last named port conduits.

3. In a built up U type engine cylinder block in combination two cylinder barrels provided with a. common combustion chamber, a top deck flange uniting the two cylinder barrels constituting a bridge between the two cylinders and forming part of the combustion chamber, separate water jackets for each cylinder barrel spacedfrom the top deck flange to provide water cooling space around the cylinder barrels, and means for connecting the water cooling spaces of the cylinders "and for providing cooling space under the bridge and for completing the closure between the cylinder water jackets and the top deck flange consisting of a water jacket extension piece.

4. In an engine cylinder block according to claim 3, the top deck flange being of minimum thickness in order to provide for rapid heat dissipation and means to provide adequate stock for tapped stud holes in the flange at points where these are required consisting of bossed stud plugs pressed into holes in the flange at points where the tapped stud holes are required and means for preventing the plugs from turning.

5. In a built up engine cylinder block in combination, a cylinder barrel of steel tubing with walls of minimum section throughout its length, a separate hold down flange secured towards one end of the cylinder barrel, a separate top deck flange secured at the other end thereof, ports in the cylinder wall at points intermediate of the flanges, a separate port ring surrounding the ports and secured to the cylinder barrel, a water jacket extending between the aforesaid flanges and provided with similar coincidental ports in its walls, and a port chamber surrounding the water jacket in the zone of the ports.

6. In a built up engine cylinder block, a plurality of cylinder barrels, a top deck flange uniting the cylinder barrels, a tubular water jacket surrounding each cylinder barrel, and means constituting a cooling jacket for the top deck flange and connecting the tubulanwater jackets to the top deck flange consisting of a water jacket extension piece.

7. In a built up engine cylinder block having complementary cylinders with a common combustion chamber a plurality of cylinder barrels, a top deck flange uniting the cylinder barrels and forming part of the combustion chamber, separate tubular Water jackets for each cylinder barrel and a water jacket extension piece connecting together the water jackets of the cylinder barrels and forming a water jacket for the top deck flange.

FRED G. SHOEMAKER. 

